i.MX 8M Plus, video encoding streams

[manc]

Are 4x 1080P60 video encode streams supported through USB (hub) only ?

The other thread answers the video encode limits implying the NXP doc's 1x 4k60 worth of video encode can be divided into 4x 1080p60 streams (without overhead from encoding multiple streams).

? But, are there other limitations in the video encode chain which limits the video encoding streams ? Such as passing all the data through the USB bus. By other limitations, I don't mean USB bandwidth, but whatever internal pathway in the SoC which the data needs to go through to get to the video encode block.

Another thread mentions i.MX 8M Plus supports 4x 1080P60 H.265 simultaneously, 2 MIPI + 2 USB.

Solved: How many video streams can the i.MX 8M Plus can en... - NXP Community

ED: added encode to subject like the other linked thread. Clarified intent with more details.

[brian14 · Accepted solution]

Hi @manc, 

Thank you for the clarification!

Yes, you can encode with H264 or H265 4 x 1080p60 using the VPU (hardware acceleration) from the iMX8MP. But take care about the bandwidth provided by the USB, especially if you are looking to use UVC Cameras.
Here is an article to illustrate the problems that you may have used multiple UVC Cameras.
Multiple UVC cameras on Linux: an unexpected challenge – The Good Penguin

I hope this information will be helpful.

Have a great day!

[manc]

I forgot to mention I'm asking about

video encoding streams like the referred topic vs video output streams.

And I don't see an option to edit the topic.

ED:

Found that editing original post, allows editing the subject.

[brian14]

Hi @manc, 

I reviewed this case in detail and here I will explain some points:

1. On the iMX8MP there is no specific support to transmit video using the USB C, therefore, to effectively transmit video by USB C you will need to add extra hardware that supports the ALT MODE for USB C and multiplex the output from video signal.
2. The video signal will be provided by the HDMI PHY with the capability to provide one display up to 4k30.

I hope this information will be helpful.

Have a great day!